Pneumatic tool



Nov. 27, 1928.

W. J. SPENCER PNEUMATIC TOOL Filed Jan. 5, 1926 Patented Nov. 27, 1928.

UNITED STATES WILLIAM JACKSON SPENCER, OF TROY, IDAHO.

PNEUMATIC TOOL.

Application filed January 5, 1926. Serial No. 79,887.

My invention pertains to the class hoists, and variety jacks, and comprises a vertical cylinder slidably mounted over an upright piston, and a base or stand for support of the piston, together with means for admitting compressed air into the cylinder and discharging it therefrom My object is to provide a simple and inexpensive jack that can be quickly operated by compressed air, and one that will retain its charge of air for a considerable period after admission is cut ofi.

How 1 attain my object will be readily understood from a perusal of the following description, and a study of the accompanying drawings, in which Fig. l is aside elevation when jack is in its normal position of rest.

Fig. 2 is a plan view or view from above. h

Fig. 3 is a combination of partial rear View and partial vertical section along the line X Y of Figs. 1 and 2, when handle 1S removed and cylinder somewhat raised and cut away so as to expose the piston and its construction. Fig. 4 is an enlarged partial view of the cylinder, showing a vertical section through the center of its front side and the recesses therein for engagement with the side lift, whilst Fig. 5 is an enlarged view of said side lift.

ln fuller explanation, a vertically slidable cylinder 1 is mounted to telescope over a piston 2 rigidly secured to the upper end of an upright shaft 3 which has its lower end firmly fixed in a boss 4: on the bottom or base 5 of a stand 6, which stand has its two opposite sides 7 vertically elongated and vertically and parallelly grooved on their opposing or inner faces so as to form a pair of rigid guides 8 for engagement with a corresponding pair of vertical guide-bars 9 secured to opposite sides of said cylinder or formed integral therewith.

The bottom of the stand 6 is elongated forwardly so as to form a toe 10 for the better support of the cylinder in an upright position in certain off-center operations, in which instances the load, instead of being carried centrally over the cylinder on the head 11 thereof, or on the shoe .12 secured thereon, is supported on a foot or side lift 13 adjustably mounted on the front side of the cylinder w midway between the guide-bars 8, said foot tween said recesses,

a corresponding series of projections 16 bethe wall of the cylinder being thickened on either side of said recesses at 17 to stiffen the same against distortion from the strain or cramping effect of the side l ft, and to prevent the shoe from slipping sidewlse, as it might otherwise sometimes do.

By extending the thickened portions 17 sufiiciently forward and so deepening the recesses 15, the projections 16 may be eliminated and the foot 13 supported on the partitions between the recesses. Y The shoe 12 may be formed integral with the cylinder head 11 or be a separable piece swiveled thereon as shown at 18, a recess 19 being formed in its under side and a correspondmg projection 20 formed on said cylinder ead for engagement with said recess, an annular groove 21 being provided in said proection for engagement with a screw or pin 22 inserted through the wall of said recess, by which means the shoe will be kept companion to the cylinder. But other suitable means may be employed for mounting said shoe 12.

To prevent the lifting foot or side-lift 13 from becoming detached and misplaced or lost in consequence, a hole 24 is provided through the end of the hook 14, and a series of holes 25 to register therewith provided through the cylinder portions 17, a pin 25 being inserted through said holes; but any other suitable method may be employed, as a chain secured at its one end to the shoe and at its other end to the cylinder or the stand.

The head of the cylinder may be cast integral with the walls, but I prefer to make it separate and secure it in some suitable manner to said walls, as for instance as shown at 26, where it is shown as threaded on its periphery and screwed into the end of the cylinder. But it may be made as a cap, threaded internally and screwed on the end of the cylinder, which in such case would be threaded externally. But it may also be made as a flange and bolted to the cylinder end which would then be correspondingly fashioned to receive it. To prevent the cylinder from being accidentally blown off the piston by admission of excess of air, a ring 27 is rovided and secured in the bottom of the cy inder in any suitable manner, in the drawings shown as threaded and screwed in in the same fashion as the cylinder head. It may, however, be dispensed with, a series of pins or screws inserted through the cylinder walls being substituted therefor; or a series of lugs may be used instead, projecting within the walls and made fast thereto. It may be in the form of a narrow annular ring, as shown, or in the form of a disc or washer centrally pierced by a hole of diameter only large enough to admit the piston 1'O( The piston 2 I prefer to make of washers centrally disposed about the upper end of the piston-rod 3, which end is turned away so as to form a shoulder 28 to support them, and is further threaded and furnished with a nut 29, by means of which they are firmly clamped in lace.

he lower disc or washer 30 is very stiff and preferably made of metal, and slightly smaller in diameter than the bore of the cylinder. l I

Superimposed on said washer 1s a series of more or less flexible washers, preferably of rather stiff leather, and of diameter closely fitting the'cylinder, and capped by a soft and very pliable washer 31, also preferably of leather and considerably larger in diameter, its periphery being turned up so as to give it a cup or saucer shape, Within wlnch upturned portion is placed an expansive ring 32, which ring presses against said upturned part of washer and forces it tightly against the cylinder, effectually sealing the joint between piston and cylinder. Between the piston and head of the cylinder is smeared a plentiful supply of grease or heavy oil, which when air is introduced under pressure immediately is forced into all accessible crevices, thus still more effectually sealing the aforesaid joint, and in addition thoroughly lubricating the contact surfaces of cylinder and piston.

The nut 29, or the end of the piston-rod if the nut be screwed down sufficiently, prevents the cylinder from descending far enough to strike the piston and accidentally distort it, or to permit the piston to cover the air inlet 33 and thus prevent the admission of the air, as would otherwise occur when the cylinder was fully lowered, said air inlet being conveni'ently located at some point in the cylinder wall immediately below the head. But it may be located in the head if such location be found preferable. It may be in the form of a hole through a boss on the cylinder or a pipe screwed into the same, as shown at 33. It may be fitted with a suitable check valve to prevent the escape of the air charge, a suitable releasing or discharge valve being provided conveniently near by in the cylinder head, or in the cylinder wall; or it may be connected as shown in the drawings by a flexible tube or hose 34 to releasing valve 35 and a check valve 36 attached to the handle-bar 37 of an adjustable handle or tongue 38 whose lower endis hinged on a rod or bolt 39 passed through holes in lugs 40- and 41 cast on the bottom of the stand at the rear thereof. Braces 42 are secured to the handle or tongue, which in the present instance I have chosen to construct of two bars of metal spaced a small distance apart with a plunger-rod 43 between them, which braces have their free ends pierced with a hole through which passes the rod 39, by which means the tongue is kept in sidewise alignment, and at the same time so hinged as to have free vertical movement.

The upper end of the plunger-rod 43 is furnished with a ball or knob 44 as a hand grip for its movement back and forth along the tongue, passes through a hole in the handle-bar 37 and terminates at the lower end in a plunger or pawl 45 in engagement with a quadrangular ratchet 46 provided at the middle rear of the base of said stand 6 for the purpose. A sprin not shown, encircling the plunger-rod, preferably just above the plunger, and held in place by a stop suitably placed, is used to hold the plunger in engagement with the ratchet. By pulling on the knob the plunger is released and the tongue free for adjustment in a vertical plane. Figs. 48 and 49 indicate webs stiffening the stand base. For the readier shifting of the jack, a pair of rollers 47 are provided, one on each side between lugs 41 and 42, and loosely journaled on rod 39, and just clear of the floor. By depressing the handle-bar the jack, when not under load, is tilted backward until the rollers rest on the floor, when it is easily moved about on them.

The operation of the jack is exceedingly simple. Being designed chiefly for use in garages, it is merely shoved under the load, usually a car, the check Valve, supposedly fitted to receive the nozzle of an air line, is connected-by such to an air reservoir, the releasing valve is closed, and air is turned on, forcing the piston and cylinder head apart causing the cylinder to rise to the load and carry same with it.

To lower the load and remove the jack, the releasing valve is opened and the air allowed to escape until the load comes to rest by gravity, when the jack is free to be shifted or removed. Having thus described my invention and its mode of operation, I claim the following as new and patentable, and pray that Letters Patent be granted me thereon:

1. In a pneumatic jack, and in combinatron, a supporting stand, an upright shaft or piston-rod secured thereon, a piston secured to the upper end of said shaft, a cylinder telescoping over said piston, upwardly extending sides to said stand on opposite sides of said cylinder, vertical and parallel grooves in the opposing faces of said upwardly extending sides, and forming guides or guideways therein, a pair of vertical and parallel gulde-bars on said cylinder, one on either side thereof, for engagement with said guideways a vertical series of recesses or pockets in the front wall of said cylinder through said handle-bar,

midway between said guide-bars, a removable foot or side-lift supported by said recesses and provided with a rearwardly and downwardly extending projection for engagement therewith, a quadrangular ratchet at the middle rear of the base of said stand and fast to the bottom thereof, a two-piece handle or tongue hinged to said ratchet and straddling the same, a handle-bar at the outward and free end of said tongue, a hole a plunger-rod through said hole and extending longitudinally of said tongue, between the two members thereof and having a knob or other suitable gripping device or handle at its outer end, and terminating at its lower end in a plunger or pawl having engagement with said ratchet, means for holding said pawl in engagement with said ratchet, a lifting shoe or load support swivelled on the head of said cylinder, means for swivelling said shoe and for retainin it in place, an air inlet in the upper end ofsaid cylinder immediately below the head thereof, a connected air inlet and air outlet valve on said handle-bar, and having flexible hose connection with said inlet in said cylinder, lugs on said stand at the rear of the bottom thereof, a pair on either side, holes through said lugs and said ratchet, rollers between said lugs, one on either side and between each pair thereof a pin or rod through said holes and said rollers and forming a journal for said rollers and a hinge-pin for said tongue, and a projecting toe-portion at the front of said stand, substantially as described and for the purposes set forth.

In a pneumatic jack, the combination of a supporting stand mounting an upright shaft havin a piston secured to its upper end, a vertically slidable cylinder in telescopic engagement with said piston, a vertically parallel pair of guide-bars on said cylinder, one on either side thereof, upwardly extending and oppositely placed sides to said stand, one on either side of said cylinder, and havin their opposing faces vertically and paralIell grooved for engagement with said guidears, a vertical series of recesses or pockets in the front of said cylinder midway between said guide-bars, an adjustable foot or side-lift carried by said cylinder provided with a rearwardly and down wardly projecting portion having engagement with said recesses, a removable shoe swivelled on the head of said cylinder, means for securing said shoe in place, means for admitting air to said cylinder above said piston, and means for discharging it therefrom, a pair of rollers at the rear of the base,

of upwardly extending portions or arms,

one on either side and oppositely placed, and having their inner faces vertically and parallelly grooved an upright piston-rod rigidly secured in the base of said stand and centrally placed between said arms, a piston mounted on the upper end of said piston-' rod, a vertically slidable cylinder enclosing said piston and in telescopic engagement therewith, a vertically disposed pair of parallel guide-bars on the outer wall of said cylinder, one on either side thereof, and in sliding engagement with said arms within said grooves therein, a vertically disposed series of pockets in the front of said cylinder wall midway between said guide-bars, an adjustable side-lift carried by said cylinder and having engagement with said pockets, and supported by the partitions between them, means for admitting air into said cylinder and means for discharging the air therefrom, and means for preventing the cylinder from being thrown from said piston.

4. In a pneumatic jack the combination of a supporting stand, a vertical piston-rod secured in said stand, a piston at the upper end of said piston-rod, a cylinder telescoping over said piston, a vertically parallel pair of guide-bars on said cylinder and on opposite sides thereof, a pair of uprights on said stand, one on either side thereof and having their opposing faces vertically grooved for engagement with said guide-bars, and inlet and exhaust ports in the upper part of said cylinder.

5. In combination in a pneumatic jack, a supporting stand, a pair of uprights on said stand, one on either side thereof, vertical grooves in the inner or opposing faces of said uprights, a piston mounted on said stand, a cylinder vertically telescoping over said piston, guide-bars on the sides of said cylinder and having engagement with said grooves, a vertical series of pockets in one side of said cylinder and midway between said guide-bars, and a'lifting foot carried b said cylinder and having engagement with said pockets by means of a rearwardly and downwardly extending projection or hook at its upper rear portion.

WILLIAM JACKSON SPENCER. 

